This report, published by the CDC is an updated and abridged version of the “1999 Technical Appendix” and focuses on information for the 2002 data file. This “Appendix” is also included in Vital Statistics of the United States, 2002, Volume I, Natality”. Reference will be made to the “1999 Technical Appendix” for historical discussion of the variables, definitions, quality, and completeness of the birth data. This report supplements the “Technical Notes” section of “ Final data for 2002” and is recommended for use with the public-use file for 2002 births, available on CD-ROM for NCHS, and the tabulated data of “Vital statistics of the United States, 2002, Volume I, Natality.